Atlas of the underworld: Slab remnants in the mantle, their sinking history, and a new outlook on lower mantle viscosity

• DOI: 10.1016/j.tecto.2017.10.004
• Publication Date: 2017-10-19T06:26:59Z
• Authors: Douwe G. van der ...; Douwe J.J. van Hi...; Wim Spakman
• Keywords: Slab; Hotspot (geology); Slab window

Across the entire mantle we interpret 94 positive seismic wave-speed anomalies as subducted lithosphere and associate these slabs with their geological record. We document this Atlas of Underworld, also accessible online at www.atlas-of-the-underworld.org, a compilation comprising subduction systems active in past ~ 300 Myr. Deeper are correlated to older records, assuming no relative horizontal motions between adjacent following break-off, using knowledge global plate circuits, but without reference frame. The longest actively subducting identified reach depth 2500 km some have impinged on Large Low Shear Velocity Provinces deepest mantle. Anomously fast sinking occurs regions affected by long-term plume rising. conclude that slab remnants eventually sink from upper core-mantle boundary. range subduction-age versus – lower is largely inherited history subduction. find significant variation average speed slabs. At top speeds 10 40 mm/yr, followed deceleration 10–15 mm/yr down depths around 1600–1700 km. In interval, situ time-stationary rates suggest 20 30 4–8 increasing 12–15 below 2000 This corroborates existence zone do not observe (> 60 My) stagnation, excluding stagnation due compositional effects. Conversion profiles viscosity shows general trend increases which slowly decreases deep variance most published derived different observations, agrees qualitatively recent suggested material experiments.